Gas stoves are commonly used in commercial and domestic kitchens. One problem with the use of gas stoves in restaurants is that the chefs often leave the burners burning when they are not in use, and this wastes fuel. Also, gas stoves used domestically present a hazard when the main gas valve is left open and the pilot light is out.
In an effort to solve this problem, various mechanical devices and linkages have been proposed for shutting off the supply of gas to the burner when a utensil is not on the burner. Unfortunately, many of the mechanical devices are relatively complex and are subject to sticking or fouling when contaminated by greases and other cooking materials. Also, it is difficult or impossible to retrofit a mechanical mechanism of this type onto an existing burner.
Chen U.S. Pat. No. 4,391,265 discloses a gas range in which a utensil actuates switches to control a motor. The motor can move the gas valve between high flame and low flame positions. This does not solve the problem of excessive gas utilization or the danger imposed by an unlit pilot light.